Method and apparatus for erecting carton blanks



METHOD AND APPARATUS FOR ERECTING CARTON BLAN'KS Filed March 9, 1967 May 12, 1970 AKE E. EDKVIST 4 Sheets-Sheet 1 INVENTOR AKE EVALD EDKVIST May 12, 1970 AKE E. EDKVIST 3,511,139

METHOD AND APPARATUS FOR ERECTING CARTON BLANKS Filed March 9. 196'? 4 Sheets-Sheet 2 INVENTOR AKE EVALD EDKVIST May 12, 1970 AKE E. EDKVIST 3,511,139

METHOD AND APPARATUS FOR ERECTING CARTON BLANKS Filed March 9. 1967 4 Sheets-Sheet 5 INVENTOR AKE EVALD EDKVIST METHOD AND APPARATUS FOR ERECTING CARTON BLANKS Filed March 9. 1967 May 12, 1970 AKE E. EDKVIST 4 Sheets-Sheet 4 INVENTOR AKE EVALD EDKVIST United States Patent METHOD AND APPARATUS FOR ERECTING CARTON BLANKS Ake Evald Edkvist, Kaglinge, Lockarp, Sweden, assignor to Palson Corporation AB, Malmo, Sweden Filed Mar. 9, 1967, Ser. No. 621,871

Claims priority, application Sweden, Mar. 14, 1966,

3,343/ 66 Int. Cl. B31b J/44, 1/28, /26

U.S. Cl. 93-51 2 Claims ABSTRACT OF THE DISCLOSURE SUMMARY OF INVENTION Conventional methods and apparatus for the erection of carton blanks have been unnecessarily circumstantial while involving lock flaps of complicated construction. These disadvantages are overcome with the present in vention.

The method according to the invention is characterized in that the carton blank in initial position, prior to erection, on the coated portions thereof which are to lie in contact with each other and to fix the erected carton, is subjected to jets of hot air to plasticize the coating to make it tacky over substantial areas of said portions. The erection of the carton is then started and said portions with their tacky coating, are moved into planar surface contact with each other and subjected to pressure in a direction generally perpendicular to said portions. The tacky coating is then allowed to cool to complete the erection of the carton.

The apparatus for carrying out this method is characterized by a cooperable punch and die; and hot air supplying means provided with nozzles which are directed to the plane, and open on either side of the same plane, in which the planar carton blank, in initial position, is applied between the punch and the die before the punch is moved towards and through the die for erection of the carton blank.

The invention will be described below with reference to the accompanying schematic drawings in which:

FIG. lis a perspective view of an embodiment of the apparatus according to the invention in an active position;

FIG. 2 shows the apparatus in another active position;

FIG. 3 is a perspective view of a carton erected by means of the apparatus according to FIGS. 1 and 2;

FIG. 4 is a perspective view of another embodiment of the apparatus according to the invention in an active position;

FIG. 5 shows the apparatus in another active position;

3,511,139 Patented May 12, 1970 FIG. 6 is a perspective view of a carton erected by means of the apparatus according to FIGS. 4 and 5.

The two embodiments of the apparatus according to the invention as illustrated in the drawings are very similar and therefore will be described in common. The differences between them will be explained as they ap pear. These differences depend on the different types of cartons to be erected by means of the apparatus. The apparatus comprises a combination of erecting means in the form of a punch 1 and a die 2, 2' and hot air supplying means provided with nozzles 3 and 4. The nozzles are directed to a plane, and open on either side of the same plane, in which a planar carton blank 5, 6, respectively, is to be applied between the punch 1 and the die 2 before the punch 1 is moved towards and through the die 2 to erect the carton blank 5 0r 6. The plane in which the carton blank 5 or 6 is applied for erection is defined by supporting and folding means in the form of heads 7, 8, respectively, on the upper surface 9, 10, respectively, of which the planar carton blank 5, 6, respectively, is placed before it is erected. The die 2, 2 comprises a rectangular frame and the punch 1 a rectangular plate 11 which is connected to a suitable driving means (not shown) and reciprocable with a certain play through a cavity 12 in the die 2. The heads 7 and 8 forming the supporting and folding means are placed in the corners of the frame. The heads 7 consist of low quadrangular uprights and the heads 8 of short, round studs arranged as will be described more in detail below.

The mouths of the nozzles 3, 4 are located in or adjacent the supporting and folding means formed by the heads 7, 8 on the upper surfaces 9, 10 of which the planar carton blank 5, 6, respectively, is placed and subjected to hot air treatment and a first folding operation when the carton blank 5, 6 is erected as the punch 1 moves through the die 2. The nozzles 3 are drawn through the bottom of the frame up to the upper surface 9 of the supporting and folding means (FIGS. 1 and 2), or adjacent the upper surface 10 (FIGS. 4 and 5) into which surfaces the nozzles 3 open to heat, by means of hot air, the under surface of corner flaps 13 or corner panels 14 placed on the supporting and folding means, the heads 7, 8, respectively. The nozzles 4 open slightly above said upper surface to heat the upper surface of those panel areas adjacent said corner flaps or corner panels which form sidewalls of the intended carton. Below said upper surfaces 9, 10 of the supporting and folding means formed by the heads 7, 8, respectively, at two opposite sides of the die 2, are folding means 16, 16' in the form of first surfaces which are depressed in relation to said upper surfaces 9, 10. At two other sides of the die 2 extending at an angle to said first sides, below said upper surfaces 9, 10 and said first, depressed surfaces 16 are further folding means 17, 17 in the form of depressed second surfaces which, as appears from the drawings, incline in a direction from the outer periphery of the die 2 to the inner periphery thereof formed by the cavity 12. Folding surfaces 16, 16' are employed to fold panels 18, 18' While folding surfaces 17, 17' are employed to fold panels 19, 19' which extend between panels 18, 1 8' and are adapted to be connected thereto by means of the flaps 13 or panels 14 respectively. In addition, surfaces 16, 16 lie in planes between forming head surfaces 9, 10 and folding surf-aces 17, 17. The play between the punch 1 and the die 2 is from two to three times as large as the thickness of the carton blank and should be so adjusted that the punch 1 can exert a pressure against the flaps 13 and panels 14 between the punch and the die to secure these fiaps and panels safely to the panels 19, 19' of the carton.

For erection of the planar foldable carton blank 5 or 6 and fixing the erected carton 20', 21, respectively, formed by the folding and erecting operation, the blank, which has a heat sensitive coating and becomes tacky by heating, is advanced in planar condition to the erecting position on the upper surfaces 9, 10 of the heads 7, 8, respectively. The heat sensitive coating on the carton blanks 5, 6 may be of any type known and will not be described in detail here. The carton blank has preferably such a coating both on the inside and outside of the intended carton. Prior to erection, the carton blank 5, 6, on the coated surfaces thereof which are to lie in contact with each other and are to fix the erected carton, is subjected to jets of hot air from the nozzles 3, 4 to plasticize the coating on substantial areas of these surfaces, the under surfaces of the flaps 13 and panels 14, and are-as of the upper surfaces of the panels 19 adjacent the corner flaps 13 and corner panels 14, respectively. After that the erecting operation is started by moving the punch 1 in the direction of the arrow 22 indicated in FIGS. 1 and 4, whereby said punch 1 pushes the carton blank 5, 6 through the die 2 and 2' and its cavity 12 and the heads 7, 8 first fold the flaps 13 and panels 14, respectively, upwards, whereupon the folding means 16, 16' fold the panels 18, 18' in the same direction While the panels 13 are swung inwards to a position close to the panels 19, 19 and the corner panels 14 are doubled along a diagonal line 23. The folding means 17, 17' thereupon folds the panels 19, 19 upwards and when the carton passes through the cavity 12 of the die 2 the panels 19, 19' are pressed against the flaps 13 and the panels 14, respectively, and the plasticized areas of the coating applied on the panels 19, 19 and on the flaps 13 and panels 14, respectively, are fused together. When these areas have been cooled upon passage of the carton through the die, they solidify and secure the panels 18, 18' and 19, 19' safely together at the corners of the carton and fix the carton in erected position (FIGS. 3 and 6). The pressure exerted on the areas to be fused together is generally perpendicular to the surfaces. The cartons pass from the die 2, 2' to a delivery station where the erected cartons are removed from the apparatus.

The nozzle arrangement described above may be used to advantage if the carton blank to be erected by the apparatus of the invention is provided with a heat sensitive coating on one side only. In that case one nozzle in each pair of nozzles will heat and thus plasticize the coating on the coated surface of the blank while the other nozzle in each pair of nozzles will heat those areas of the uncoated surface which are to be connected with the plasticized areas of the coating on the other surface. This gives a much safer connection than if only the coated area were heated.

The invention affords great advantages in the erection of cartons of any kind but the advantages become particularly apparent when cartons or boxes of corrugated cardboard are to be erected and fixed in erected position by means of the present invention. Application of adhesive becomes unnecessary. If welding is carried out by means of heated welding dies, which to produce the desired efiect, require heavy compression of the carton parts to be heated and connected together, the rigid, insulating and shock absorbing properties of corrugated cardboard will be destroyed. These inconveniencies are eliminated with this invention which in practice only requires a light compression which does not affect the properties of corrugated cardboard.

In the foregoing the invention has been described with reference to a carton blank which in erected state forms an upwardly open carton. However, there is nothing to prevent cartons with covers or lids from being erected and fixed in accordance with the invention. The modification which the apparatus of the invention may require for this purpose is within the scope of the invention such as indicated in the appended claims.

What I claim and desire to secure by Letters Patent is:

1. Apparatus for forming a carton from a planar foldable blank, the carton being of the type including a base and at least two sidewalls extending at an angle to each other and projecting upwardly from the base and terminating in a common corner portion interconnecting both wall portions, the corner portion having a heat sensitive adhesive coating preplaoed on opposite faces thereof and the corner portion being secured to one of the walls by means of the heat sensitive adhesive coating thereof; the apparatus comprising a die having a die cavity through which the blank is forced to form the base of the carton, said die further including two forming members defining portions of said die passage and extending at an angle to each other to fold portons of said blank to form the walls of the carton upon passage of the blank through said die cavity, said die further including a forming head located between said forming members for folding the corner portion of the blank upwardly and laterally while the blank is being forced through said die passage, said forming members and forming head having upper surfaces which engage and support the blank during folding upon passage through said die cavity, the surface of the forming member being situated at a level between the surface of the other forming member and the surface of the forming head such that the walls and corner portion of the blank are folded in sequence relative to each other as the blank is forced through the die cavity, a first nozzle having a mouth situated closely adjacent said forming head to conduct a stream of hot air to the adhesive coating on the corner portion immediately prior to passage of the blank through the die, a second nozzle extending in the forming head and having a mouth terminating in the surface of the forming head to conduct a stream of hot air to the underface of the corner portion, said first nozzle being located above said second nozzle to conduct a stream of hot air on the upper face of the corner portion.

2. Apparatus for forming a carton from a planar foldable blank, the carton being of the type including a base and two pair of opposite and generally parallel side walls projecting upwardly from the base and terminating in common corner portions in connecting adjacent walls and with the corner portions being secured to one of the walls respectively by means of a heat sensitive adhesive preplaced on the corner portions; the apparatus including a die having a die cavity through which the blank is forced to form the base of the carton, said die further including two pairs of opposite and parallel forming members for forming the opposite parallel side walls of the carton, the upper surfaces of one forming member in each pair of adjacent forming members being inclined downwardly towards the die cavity to an elevation below the elevation of the surface of the other forming member and said forming members being such that the walls of the carton formed by each of said one forming members are folded into position after the corner portions and other walls are folded, and four nozzles having their mouths respectively positioned adjacent the four forming heads to conduct hot air to the corners of the blank to render the heat sensitive adhesive on the corners of the blank tacky immediately before the blank is forced through the die cavity.

(References on following page) References Cited UNITED STATES PATENTS Moore 9351 X Coy 9351 Grabus 9359 Gaubert 9351 Samsing 9351 Goss 935 1 Kannengiesser 9384 Govatsos 935 1 Dunn 9351 Wainberg 9351 6 Wainberg 93-51 Rein 9355.1 Rumberger 9336 Benzon-Petersen 9359 Gordon 9359 Berney 9336 Hall 9351 X WAYNE A. MORSE, JR., Primary Examiner US. Cl. X.R. 

